A personal wireless area network (WPAN) is a network used for communication among computing devices (for example, personal devices such as telephones and personal digital assistants) close to one person (the devices may or may not belong to that person). The reach of a WPAN may be for example a few meters. WPANs may be used for example for interpersonal communication among personal devices themselves, or for connecting via an uplink to a higher level network, for example the Internet.
The WEE 802.15.3 Task Group 3c (TG3c) was formed in March 2005. TG3c is developing a millimeter-wave (mmWave) based alternative physical layer (PHY) for the existing 802.15.3 Wireless Personal Area Network (WPAN) Standard e.g., IEEE 802.15.3-2003. This mmWave WPAN may operate in a band including the 57-64 GHz unlicensed band defined by FCC 47 CFR 15.255 and other regulatory bodies and may be referred to as “60 GHz”. The millimeter-wave WPAN may allow very high data rate (e.g., over 2 Gigabit per second (Gbps)) applications such as high speed Internet access, streaming content download (e.g., video on demand, high-definition television (HDTV), home theater, etc.), real time streaming and wireless data bus for cable replacement.
However, a mmWave communication link is significantly less robust than links operating at lower frequencies (e.g. 2.4 GHz and 5 GHz bands) due to the Friis transmission equation, oxygen absorption and high attenuation through obstructions. In addition, the mmWave communication link may use a directional antenna and/or antennas array to increase the communication range. The use of a directional antenna makes a link very sensitive to mobility. For example, a slight change in the orientation of the device or the movement of a nearby object and/or person may disrupt the link.
In mmWave network forwarding data frames from a sending station to a receiving station by a forwarding station may consume a lot of memory resources and computing resources in order to forward the data frames to the receiving station and to provide block acknowledge frame to the sending station.
For example, the forwarding station may need to convert the address of the station and to encrypt or decrypt the data frame if desired. For example, if the data from the source station (STA) A to the destination STA B is delivered using the BSS services provided by Forwarding STA (Forw STA) then the Forw STA may be first delivered from the STA A to the Forw STA and then the Forw STA may deliver it to the destination STA B. The point to point approach implies that a STA may send a frame to the Forw STA with the Forw address in the first address field (e.g., Addr1) and the STA B address in the second address field (e.g., Addr 3). The frame sent by STA A may be acknowledged by Forw STA, if desired.
In the WiFi networks of mmWave spectrum like 60 MHz the propagation distance is short due to small size of antennas, therefore forwarding of frames may provide solution to extend the propagation distance. The problem of the known point to point based mechanism of forwarding is that it needs substantial amount of memory and processing time to be spent in the forwarding station which may further consume a lot of battery power.
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